In many cases of valve controlled flow it is indicated to lock or immobilize the valve to prevent unwanted shutoff or loss of fluid, especially where the valve is located in a place there it is accessible to unauthorized persons.
One way to do this is to place a built-in lock in the valve, but heretofore, the lock can be put out of use merely by hitting the valve handle or stem with an implement, breaking the lock.
This invention proposes to eliminate breaking of the lock by placing it where it cannot be affected by such adverse action.